A 20 GHz microwave heater for digital microfluidic

Abstract

This paper reports on a microwave heater at 20 GHz for digital microfluidics. It allows rapid heating of nanoliter fluid samples and simultaneous temperature monitoring by correlating the reflection coefficient of the heater with the temperature dependency of the relative permittivity of the lossy fluid under consideration, in this case demineralized water. Microwave heating was performed with power levels of 20 and 23 dBm at the on-wafer probe tips on samples of 500 nL. Temperature measurements were carried out with a miniaturized type K thermocouple, and a platinum resistor to monitor the reference temperature. Microwave and thermal performances have been characterized using multi-physics software, and measurements obtained with a large signal vector network analyzer showed good agreement with simulated data. An average heating rate of 20 °C/s was observed during the first 4 s of the heating process.

A syndromic diagnostic assay on a macrochannel-to-digital microfluidic platform for automatic identification of multiple respiratory pathogens

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A Stripline-Based Integrated Microfluidic-Microwave Module

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Design and Comparison of Resonant and Non-Resonant Single-Layer Microwave Heaters for Continuous Flow Microfluidics in Silicon-Glass Technology

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